Though the band has had changes over the years, frontman Billy Corgan remains as solid as ever. For the band’s “In Plainsong” tour, you can expect to hear songs that have been stripped down for what’s being described as an “acoustic-electro” set. Corgan is joined by drummer Jimmy Chamberlin after more than six years, and Jeff Schroeder, who replaced longtime guitarist James Iha back in 2007. Songstress Liz Phair opens.